论文标题
罗森塔尔的空间被重新审视
Rosenthal's space revisited
论文作者
论文摘要
令$ e $为$ [0,1] $上的重新安排不变性(r.i。)功能空间,让$ z_e $由$(0,\ infty)$上的所有可测量函数$ f $组成,使得$ f^*χ_ {[0,1] [0,1]} \ in e $和$ f^*χ_ $ _ $ f^$ n l^$ n l^[1,}}。我们揭示了对应于空间$ z_e $的广义Rosenthal空间的属性之间的密切连接,以及在$ e $中的独立对称分布式随机变量的行为。获得的结果用于考虑$ [0,1] $和$(0,\ infty)$之间存在的同构的问题。利用了不相交序列的特定属性,我们确定了$ [0,1] $`close''上的一类新的R.I. \ Space,to $ l^\ infty $,这对R.I. \ spaces in $(0,\ infty)$均未是同构。特别是,该属性由lorentz空间$λ_2(\ log^{ - α}(e/u))$共享,其中$ 0 <α\ le 1 $。
Let $E$ be a rearrangement invariant (r.i.) function space on $[0,1]$, and let $Z_E$ consist of all measurable functions $f$ on $(0,\infty)$ such that $f^*χ_{[0,1]}\in E$ and $f^*χ_{[1,\infty)}\in L^2$. We reveal close connections between properties of the generalized Rosenthal's space, corresponding to the space $Z_E$, and the behaviour of independent symmetrically distributed random variables in $E$. The results obtained are applied to consider the problem of the existence of isomorphisms between r.i.\ spaces on $[0,1]$ and $(0,\infty)$. Exploiting particular properties of disjoint sequences, we identify a rather wide new class of r.i.\ spaces on $[0,1]$ ``close'' to $L^\infty$, which fail to be isomorphic to r.i.\ spaces on $(0,\infty)$. In particular, this property is shared by the Lorentz spaces $Λ_2(\log^{-α}(e/u))$, with $0<α\le 1$.